Nevada Public Radio Listen Live

"BBC World Service"
Facebook Twitter Follow Nevada Public Radio

Support Nevada Public Radio
May 06, 2014
Podcasts

DESERT BLOOM: Emerald Ash Borer

Listen

Angela

There are so many trees out in the world, but only a relatively small number can survive, much less actually flourish, in our challenging environment. We do insist on growing some poorly fitting ones: looking around the valley, there are lots of marginal purple leaf plums, short-lived chitalpas, and even the occasional weeping willow. When I see those, I get a little incensed, since there’s no excuse for growing them in the middle of the Mojave – they only belong in places that get considerably more than four and a quarter inches of rainfall per year!

MesquiteOf course, true desert trees, like mesquite and desert willow (which is not even remotely related to the weeping one), grow and thrive here.  Even here, though, we do have a bigger selection that just those two. Included in that group are several of the ashes. You can find various kinds of ash trees growing perfectly well all around the country. I recently read that there are over seven billion ash trees growing in the US!

Arizona AshGiven the name, Arizona ash would be an obvious choice for this region, but they’re not alone. Raywood, fan-tex, velvet ash – they all tolerate desert conditions remarkably well, as long as they receive enough water and the occasional hit of compost tea. We have so few great tough shade trees in the desert; we need to keep them healthy and happy.

Not everything is so great for ash trees in this country, unfortunately. There is a pest making its way across the continent, causing devastation in its path. The only good thing about it is that it only affects ash.

This pest is a slender little insect, about ¼ to ½ inch long, colored a vivid green, that destroys ash trees. The emerald ash borer has been marching from east to west, killing its hosts.

Such a small thing, with such a pretty color, and such a terrible villain! From the time it was introduced into the US (not deliberately introduced, obviously), it has killed tens of millions of ash trees. Apparently, it arrived from Asia on packing crates in cargo ships and planes. Since its first sighting in 2002, it spread throughout the northeast and a sizeable chunk of the central United States.

To try and keep it from spreading even more than it already has, certain agencies, including the Department of Agriculture, have imposed quarantines on wood from 21 states and two Canadian provinces. This is one of the few ways to slow down its migration.

Still, it continues to spread, albeit more slowly than it would otherwise.

The difficulty is that people don’t always pay attention. I’m not sure who drew it, but there’s a cartoon that gives a good explanation of how this insect’s been able to continue its lethal journey. In this cartoon, a big man is carrying a bundle of firewood. Strolling next to him is an emerald ash borer wearing a t-shirt that says, “I’m with stupid”.

Ash borer

People who want to save a few dollars frequently carry their own firewood when they go camping. Too often, they’re bringing it from infested states where there’s now lots of dead ash wood, to places where the borer hasn’t yet been established.  

Happily, this bit of misery isn’t in Nevada – yet. Since we need to keep our ash trees alive, all of us should be careful and observant. 

As I said, it’s only up to a half inch long, so the insect itself’d be easy to miss.

It’s not the adult that causes the plant to die, however. Adults eat a few leaves, but don’t kill the tree. Its voracious babies, on the other hand, are the bad guys. If an ash has a D shaped hole in the bark, look closer. A D-shaped hole is the exit for the adults who grew from the juveniles who destroyed part of the tree’s circulatory system.

This is a real concern. If you see this kind of a hole, especially if the ash tree looks stressed, call Cooperative Extension: (702) 222-3130

For KNPR’s Desert Bloom, this is Dr. Angela O’Callaghan of the University of Nevada Cooperative Extension.

See discussion rules.

Archives

AngelaDec 13, 2014 | To Prune or Not to Prune
As winter draws near, leaves begin to fall. And the bare view may prompt some excessive pruning. It's tempting, but your plants may appreciate a little restraint. Here's Angela O'Callaghan with Desert Bloom.

NormDec 6, 2014 | Prepare Your Plants for Cold Weather
It's not cold . . . yet, but Norm says be ready and your yard will appreciate it. Don't let a cold snap cost you your investment in plants in your yard. Norm Schilling has some ideas to get ready.

AngelaNov 25, 2014 | Evergreens
As we head into the holiday season, more attention is given to 'evergreens.' Too many cones on a pine tree might be a sign of weakness. Angela O'Callaghan tells us all about evergreens on Desert Bloom.

NormNov 14, 2014 | Fall Colors
Even in the desert, Fall colors can brighten your landscape. Here's Norm Schilling with Desert Bloom.

NormOct 28, 2014 | Fall Colors - Web Only Edition
With glorious weather for our yards to fall back into bloom, Norm has some additional suggestions for color to add to the profusion of blooms for this time of year. (Web-only content)

NormOct 7, 2014 | Second Spring
The call it a "second spring" Norm Schilling has some plan ideas to make Fall colorful in your yard. He has a checklist of plants looking their best, because now is the time to plant in Southern Nevada.

AngelaSep 30, 2014 | Fountain Grass
A weed by any other name is still a weed even if it doesn't look like one. If only everything in our gardens thrived as well as weeds. Here is Angela O'Callaghan.

NormSep 15, 2014 | Desert Heat
Norm describes a significant casualty of the desert heat. There's going to be a big gap in Norm's Yard and a lesson on the reality of our desert landscape.

AngelaAug 12, 2014 | Organic Pesticides
Choosing a method for ridding your garden of an unwanted guest, be it bug or weed, is not always a simple choice. But the more you know, the better it goes. Here's Angela O'Callaghan

NormJul 28, 2014 | Lose that Lawn
We know, it's a desert out there including every place there's a lawn. Norm Schilling reminds us all the ways he wants you to consider losing the lawn... permanently.

AngelaJul 14, 2014 | Protect Fruit Trees from Birds
If you put a good deal of care into growing fruit trees, there are likely some birds who will take advantage of your effort. Here's Angela O'Callaghan.

NormJul 10, 2014 | Palm Care, Part 2
To keep, or not to keep. Norm Schilling ponders his palm trees, on this edition of Desert Bloom.

NormJun 10, 2014 | Palm Care
Norm Schilling has mixed feelings about how we use Palms in our yards. Full grown palm trees transplanted into the entry way of a mall is a common sight that tells Southern Nevadan's "something" is nearly open for business. He reminds us that those palms come with challenges.

AngelaJun 3, 2014 | Hot Weather Plants
As temperatures across the Valley begin to climb, you might be wondering what will survive in your garden in the months ahead and what probably won't. There are some 'sweet' options. Here's Angela O'Callaghan

NormMay 20, 2014 | Desert Color
Norm Schilling just got back from Belize and has some ideas for lush leaves in your desert yard. He reflects on some well suited plants to provide color and variety in this edition of Desert Bloom.

AngelaMay 6, 2014 | Emerald Ash Borer
Raising a healthy shade tree in the Mojave is not always easy. And if one particular insect makes its way here, it could get even harder. Here's Angela O'Callaghan with Desert Bloom.

NormApr 22, 2014 | The Right Plants
Our current warm spell gives the impression that some plants can thrive when they aren't really suited to our desert. Norm Schilling has some examples.

NormMar 24, 2014 | Spring Garden Party
Spring is here and the garden is blooming . . . so invite some friends to enjoy the rewards of gardening!

AngelaMar 10, 2014 | Lady Banks
If you love roses, but don't care for thorns, you may want to call on 'Lady Banks.' Here's Angela O'Callaghan with Desert Bloom.

NormFeb 26, 2014 | Signs of Spring
It may be February, but if you are paying attention, signs of Spring are visible. Dwarf peach and Mexican plum trees are in bloom. Vibrant Red Spraxis can be seen among the falling Almond blossom. Watch gardening expert Norm Schilling transplant an offshoot. Check out the slide show of photos taken from his backyard.

© 2014 NEVADA PUBLIC RADIO   
Web hosting facilities provided by Switch.